Optimization Design Of Combined Scheme Of Broken East Drilling And Periodic Water Injection In Beiyi District

In recent years,as the production rate of old wells in water flooding oilfields has increased,the number of newly drilled infill wells has increased year by year.According to the requirements of formation pressure for drilling construction,it is necessary to ensure that the formation pressure is kept at a low level during new drilling.Daqing Oilfield requires that the pressure of the injection wellhead must be reduced below 3MPa to ensure the drilling quality and drilling safety.Therefore,in the process of replenishing a new well,it is necessary to shut down a large number of injection wells in operation,which will inevitably have a great impact on the output of the corresponding wells.In order to reduce the impact of shut-in wells on production well production,it is necessary to study the corresponding shut-in technology boundary,open well recovery system,and the combination of pressure reduction and periodic water injection.Through the research in this paper,we strive to make the problem of drilling and shutting down well,so that drilling and shutting the well is not only for the efficiency of drilling and the safety of drilling,but also can further improve the development effect and development level.First,geological modeling and history fitting were performed on the East Block of the North District.Through the dynamic analysis of oil and water wells,the factors affecting the pressure drop time were initially selected as: bottom hole flow pressure,permeability,fluid viscosity,production fluid strength of connected oil wells,well spacing,effective thickness and water content.The ideal model is used to simulate the seven factors: the single factor is changed,and the influence of each factor on the pressure drop time is obtained.The sensitivity analysis method is used to study,and the weight is determined according to the change rate of the pressure drop at the same rate of change of each factor.Size,and finally based on the ideal model prediction results and actual situation analysis,determine the factors with greater impact for regression analysis.The predicted value of the pressure drop time of the actual well is calculated according to the polynomial of the ideal model plate regression,that is,the initial value,and the value is used as the initial value of the well pressure drop to set the pressure drop time in the actual model.During the simulation,some wells cannot fall to 3MPa or fall below 3 MPa in the initial time.At this time,the wells need to be adjusted to obtain the numerical simulation pressure drop time value of the final actual model.Then,according to the numerical simulation of the pressure drop time,the regression is obtained,and the final polynomial of the pressure drop time combined with the actual model is obtained.The method for determining the pressure drop time is given,and the single well shut-in technology limit program is programmed to give the drilled shut-in The technical boundaries of the system.Secondly,a cycle water injection scheme after drilling,before drilling and during drilling is established to achieve the combination of water well drilling and periodic water injection.After the drilling is completed,the water injection cycle is preferred in the periodic water injection scheme.The dynamic and static parameters of the study area are statistically analyzed to determine the characteristic parameter range suitable for the periodic injection well;the pre-drilling cycle water injection scheme is determined according to the pressure drop time and the cycle of the drilling cycle is simulated and predicted.Dynamic indicators of the dynamic hydration scheme.Finally,formulate the water injection recovery plan after the completion of drilling,and carry out the phased injection according to the different proportions of the original injection amount,restore the original injection amount,predict and compare the liquid production and oil production of each scheme;Appropriately,the forecast compares the production volume and oil production of each scheme,and optimizes the scheme that has the least impact on the yield;according to the actual block injection and the permeability gradient difference distribution of the production well,determine the way of water injection recovery,and prepare a single well.The technical limit procedure is restored,and the number of stages,phase periods and stage recovery of each type of single well recovery water injection are determined through calculation,and the technical limit of the drilling and recovery system is given.